990 heads on 402?

[VintageMusclecar]

I don't think there are any off the shelf 11-1 pistons for an open chamber 396/402??-- you may have to go with a custom set.

Given the weight and gearing of the car, I'd stick with an oval port head. I would also advise skipping the 11-1 compression ratio and shoot for 9.5 to 10-1. The power difference would be minimal and you'll have a significantly larger tuning window to help keep the engine out of detonation.

The 569 intake will work fine on the oval ports, been done countless times before. Which Holley carb are you getting to go along with the 569 intake?

[luzl78]

Eric. It’s a 4492. It’s rich peters carb and manifold